本研究利用偏光顯微鏡(polarized-light optical microscopy, POM)、掃描式電子顯微鏡(scanning electron microscopy, SEM)、廣角度X光繞射儀(microbeam wide-angle X-ray diffraction, WAXD)以及小角度X光散射儀(microbeam small-angle X-ray scanning, SAXS)、微分掃描熱卡計(differential scanning calorimeter, DSC)，探討生物可分解性高分子左旋聚乳酸(L-(+)-polylactide, PLLA)及聚羥基丁酸酯(D-(-)-poly(3-hydroxybutyrate), PHB)，加入聚丙烯酸甲酯(poly(methyl acrylate), PMA)及聚乙酸乙烯酯(poly(vinyl acetate), PVAc)形成環帶狀球晶之形貌、上表面及內部晶板排列。在PLLA中加入不同比例之PMA及改變結晶溫度，以POM觀察球晶形貌，並以DSC確認系統的相容性。接著，以環帶最規則Tc = 133 oC之樣品進一步分析，以SEM觀察球晶上表面與內部結構的晶板排列，藉由裂縫顯示出晶板排列的不連續性。接著利用synchrotron microbeam WAXD及SAXS證實在SEM觀察之晶板排列，推測出PLLA環帶狀球晶之ridge及valley分別對應內部垂直與水平的晶板。PHB以Tc = 105 oC之樣品進一步分析，透過SEM分析上表面及內部結構的晶板排列，推測PHB環帶狀球晶內部晶體排列的週期性，晶板以垂直方式排列形成ridge後再偏折並沉積至valley以水平做堆疊。最後，綜合兩者之環帶狀球晶上表面、內部結構之晶板排列及晶板堆疊的規則度對晶體堆排形成之光學現象，顯示出PLLA與PHB之間的統合性與特異性，PLLA之環帶週期先以valley形成，PHB之環帶週期則先以ridge形成，進而了解晶板週期性且不連續性的排列，建立完整3D環帶狀球晶之生長機制。

In this study, we use polarized-light optical microscopy (POM), scanning electron microscopy (SEM), microbeam wide-angle X-ray diffraction (WAXD) and microbeam small-angle X-ray scattering (SAXS), and differential scanning calorimeter (DSC) to explore the biodegradable polymer L-(+)-polylactide (PLLA) and D-(-)-poly(3-hydroxybutyrate), PHB. Add amorphous poly(methyl acrylate) (PMA) and poly(vinyl acetate) (PVAc) to analyze the ring-banded morphology, top surface, and interior lamellar assembly. Change the composition of PLLA/PMA and crystallization temperature to make the ring-banded spherulite clear, and confirm the compatibility of the blend system by DSC. The sample with the most regular ring band at Tc = 133 oC. The top surface and the interior lamellar arrangement of the spherulites observe by SEM, and the discontinuity of lamellar arrangement was revealed by the cracks. Synchrotron microbeam WAXD and SAXS confirmed the orientation of the lamellae, and it speculates that the ridge and valley of the PLLA ring-banded spherulites correspond to the interior normal and horizontal lamellae, respectively. PHB spherulites at Tc = 105 oC which demonstrate more regular ring bands will be research focus. The top surface and interior of the lamellae show the periodicity of the interior lamellar arrangement of thex PHB ring-banded spherulite. The normal lamellae assembly forms a ridge and then bending clockwise to the valley for horizontal arrangement. Finally, combining the top surface and the interior lamellar assembly with POM graphs, it shows the universality and individuality uniqueness between PLLA and PHB. We prove the periodic and discontinuous assembly of lamellae and establish the growth mechanism of complete 3D ring-banded spherulites.

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